.bash_profile and .bashrc are two bash shell config files. Where .bash_profile is a login shell config file, and .bashrc is a non-login shell file. By login-shell , we mean a shell file used during console login, (ctrl+alt+F7) ,which is .bash_profile file.
By non-login shell we mean shell used during terminal login (XTERM). Both config files are used to config bash shell to config the info written in it with login.
.bashrc is also run when you start a new bash instance by typing
/bin/bash in a terminal. both are present at home i.e ~/.bashrc and ~/.bash_profile.
If you don’t have any above file you can create it yourself.